1. Field of the Invention
The present invention relates generally to cobalt-rare earth permanent magnets. More particularly, the present invention is concerned with Sm(Co-Ti-Cu-Fe) compositions which have the improved magnetic properties of enhanced coercivity and rectangularity.
2. Description of the Prior Art
E. A. Nesbitt et al, in U.S. Pat. No. 3,560,200, which issued Feb. 2, 1971, discloses the influence of the samarium content on the magnetic behavior of Sm(Co-Cu-Fe) compositions. However, the coercive force level of 4500 Oe which is obtained by Nesbitt's permanent magnet renders the permanent magnetic insufficient for use as a permanent magnet. These conventional rare earth permanent magnets have many deficiencies in that it is necessary to age the magnets after sintering. The manufacturing process is complicated and long manufacturing times are required. Also, the magnetic powder cannot be simply stored because it rapidly oxidizes. A need, therefore, continues to exist for a method by which rare earth alloys can be prepared simply and in a manner such that they are stable to oxidation.